Rotary control device



Aug. 14, 1956 R. L. CLOONAN Ronny .CONTROL' nsvzcs Filed April. 7, 1955 fi/e n for United States Patent Ofiice Patented Aug. 14, 1956 ROTARY comm. nnvrca Robert L. Cloonan, Chicago, 111., assignor to Gaylord Products, Inc., Chicago, 11]., a corporation of Delaware Application April 1, 1955, swarm. 499,992

7 Claims. (Cl. zoo-s of the vehicle into rotation of a rotating body shaft or cable and by means of such rotation actuate an electric switch which may energize or deenergize an appropriate electric circuit to exercise the desired control.

The present invention relates particularly to a device which in response to the speed of rotation of a rotating body may energize or deenergize an electrical control circuit.

Briefly described the present invention comprises a driving rotor and a driven rotor or follower. The driving rotor is substantially triangular in shape, preferably in the shape of an equilateral triangle and the driven rotor is provided with a similar recess of larger size in which the driving triangular member loosely registers. The driven rotor circumscribes the axis of rotation of the driving rotor and is radially movable a limited distance relative to said axis. A spring switch arm bears radially upon the periphery of the driven rotor and the driving rotor and driven rotor are movably associated through the medium of a yieldable mastic materal which has a predetermined shear strength. The spring switch arm tends to urge the driven rotor toward an eccentric position relative to the axis of rotation of the driving rotor and this urging force is opposed by the frictional resistance of the driving rotor upon the driven rotor through the agency of the yieldable mastic material when the driving rotor is rotated. When this frictional resistance, which is a function of the rateof rotation of the driving rotor, overcomes the force exerted by the spring switch arm the driven rotor moves to a substantially concentric position with respect to the driving rotor and the switch arm is moved to a switch-actuating position.

The objects, advantages and features of the present invention will be apparent from the accompanying drawing and following detailed description.

Fig. 1 is a vertical sectional view of the device comprising the present invention, taken on line 11 of Fig. 2. I

Fig. 2 is a transverse sectional view taken on line 2--2 of Fig. l.

Fig. 3 is a view similar to Fig. 2 showing the parts in a different position.

Fig. 4 is a detailed perspective view of the triangular driving rotor.

z stantially cup-shaped housing having a cylindrical lateral wall 2, a closed bottom 3 and an open top. A disc 4 is mounted upon the upper edge of the lateral wall 2 and functions as a closure for the housing, providing a closed zone 5. The closure disc may be secured to the upped edge of the lateral wall 2 by cement 6 or the like.

A projection 7 extends outwardly from the bottom 3 being disposed substantially centrally of said bottom, and a similar projection 8 extends outwardly from the closure disc 4 in substantial alignment with the projection 7. Projection 7 is provided with a central .bore 9 and projection 8 is provided with an aligned bore 10 for the reception of ,a shaft 11 which is journaled for rotation in said bores.

The shaft 11 comprises the rotating drive for the device and may be connected externally to any suitable rotating body (not shown) the rotation of which is to exercise the desired control. If the device is to be used in conjunction with an automobile, the shaft 11 may be conveniently connected to the speedometer cable of the vehicle or, if desired, the shaft 11 comprise an intermediate portion of the speedometer cable itself. The projections 7 and 8 may carry external threads 12 whereby the device may be secured by female couplings (not shown) to, for instance, the speedometer cable sheath.

Within the 'zone 5, the shaft 11 may carry a driving rotor 13, shown in detail in Fig. 4. The rotor 13 may comprise a cylindrical collar 14 which may be rigidly secured to shaft 11 whereby rotor 13 will rotate with said shaft. The rotor 13 also comprises a substantially triangular plate 15 which is preferably in the shape of an equilateral triangle. At the corners of the triangular plate 15 bulbous bearing bosses 16 are carried, the function of which will be hereinafter more fully described.

A driven rotor or follower 17, shown in detail in Fig. 5, is also carried in the zone 5. The control portion of the follower 17 is provided with a substantially triangular shaped recess 18 which is preferably equilaterally triangular. The central portion of the follower 17 is also provided with a bore 19, the arrangement being such that shaft 11 is positioned in said bore and thus the follower 17 cireumscribes said shaft. The bore 19 is of a diameter materially in excess of the diameter of shaft 11 and hence the follower 17 is not only circumferentially freely movable about shaft 11 but is also radially movable relative to said shaft a distance equal to the difference in diameters of bore 19 and collar 14 of the driving rotor 13.

When the device is assembled, the triangular plate 15 of the driving rotor 13 is positioned in the triangular recess 18 and a closure plate 20 is mounted over the recess 18, said closure plate being provided with a central aperture 21 of a diameter substantially equal to bore 19 and in alignment therewith. The depth of recess 18 is greater than the thickness of the triangular plate 15 and, hence, clearance spaces 22 are provided between the bottom of the driven rotor 17 and the lower face of the closure plate 20 and the opposite faces of the triangular plate 15. In the drawing, the spaces 22 are exaggerated in size and a mastic material 23 having a relatively high shear strength is adapted to be carried upon the opposed faces of the elements at the clearance spaces. The mastic material 23 adheres to the metal opposed surfaces of the driven rotor and driving rotor and preferably has a relatively high shear strength.

The mastic material may comprise a relatively high viscosity material such as a silicone fluid, grease or paste,

but, if desired, other materials may be used such as, industrial grease or the like. However, because of the high stability of the silicones they are preferred, since their viscosity and shear strength varies very little with changes in temperature and with increases in rate of shear.

A conventional electric snap switch 24 is mounted in the zone adjacent the periphery of the rotor, 17. The switch 24 comprises essentially 'an L-shaped mounting frame 25 which is secured to wall 2 of the housing by rivets 26 or the like. A support arm 27 is secured to the frame 25 and the entire frame 25 and supportarm 27 are grounded to a conductor 28 which connects to a suitable external control circuit (not shown). An electrode 29 is carried on the frame 25 but is insulated therefrom and a conductor 30 connects said electrode to the external circuit which connects with the conductor 28. A switch arm 31, carrying a contact point 32, is disposed adjacent electrode 29, to complete the circuit between conductors 28 and 30 and thus energize theexternal circuit. A bearing arm 33 is pivoted upon the support 27 and is pivotally connected to switch arm 31. A bow spring 34 bears upon switch arm 31, and, depending upon the direction it is bowed, urges contact 32 toward or away from electrode 29. The spring 34 always maintains tension upon bearing arm 33 causing said arm to exert resilient radial pressure upon the periphery of the driven rotor 17. Depending upon the nature of the control to be exercised by the external circuit which includes switch 24, said switch may be of the normally open or normally closed type. However, for purposes of description a normally closed switch is shown which will be opened when the shaft 11 rotates at a predetermined rotational speed. s

When the rotors are stationary the bearing arm will urge the follower or driven rotor 17 to an eccentric position with respect to driving rotor 13 and shaft 11. Under predetermined operating conditions, as will be hereinafter more fully described, follower 17 will move to a concentric position with respect to shaft 11 and in so moving will actuate switch 24.

It will be noted from the drawing that the triangular plate of the driving rotor is smaller than recess 18 although of substantially similar shape. In addition, because of the sizes of the diameters of the collar 14 and bore 19 the driven rotor 17 is radially movable with respect to the plate 15 of the driving rotor 13. Hence, when the driving rotor is stationary the driven rotor will assume a position eccentric thereto because of the radial force exerted by bearing arm 33, such, for instance, as the position of the parts shown in Fig. 2.

In order to prevent the driving rotor from freely rotating within the recess 18, the distance between the axis of rotation to the central portion of an arc of a bulbous bearing boss should be greater than the distance between the ax is of rotation of the follower 17 when it is concentric with shaft 11 to the central portion of a lateral defining side of the triangular recess 18. Preferably this difierence in distances should be sufficiently great to prevent wedging of the plate 15 within the recess 18. In addition, when the triangular plate 15 and triangular recess 18 are concentric and the respective sides of the triangles thus formed are parallel the distance from the axisofshaftllfrom the centerofthearcofabulbous bearing boss 16 should be less than the distance from the axisofsaidshaftfromacorneroftherecess.

In the operation of the present device there are four forces acting, l, the'degree of adhesion of the material 23 upon the surfaces of the rotor plate 15 and the surfaces of the bottom of the recess 18 and the lower face of the plate 2!, together with the shear strength of the material 23; 2, the rate of rotation of shaft 11; 3, the rotational force exerled by the bulbous bearing bosses 16 upon the side walls of the recess 18; and 4,-the radial thrust exerted by arm 33 upon the periphery of the follower. Forces 1, 2 and 3, hereinbefore described, are opposed by force 4, and the functioning of the device depends upon the dominance of one or the other of these opposed r rm 1, 2 and s being'considered 5 single force mthisoounection).

move arm 33, follower 17 will still be maintained in an eccentric position with respect to shaft 11 even though the follower 17 will be caused to rotate. The action which takes place under these conditions is asfollows: If rotor 13 is moving in a counterclockwise direction at leastoneoftheboesesliwillexertacomponentof forcetending to move follower 17 toward a concentric position with shaft 11, that is, it will tend to cause follower 17 to move from left to right, as viewed in Figs. 2 and 3. However, the resilient force of arm 33 restrains such movement. Hence, follower 17 will slip circumferentially in a counter-clockwise direction relative to rotor 13, that is, the material 23 will be sheared, the follower moving at a faster rate of rotation than rotor 13 for an incremental period of time. However, follower 17 is dependent upon rotor 13 for its continued rotation and rotor 13 catches up with the follower and again tends to rotate the same and move it radially toward arm 33. Under the conditions stated, arm 33 restrains such radial movement, and the slipping action is repeated. Thus, as long as arm 33 (force 4) overbalanees forces 1, 2 a.nd 3, follower 17 will remain in an eccentric position and switch 24 will not be actuated.

the'rate of rotation of shaft 11 is increased, thus tncreasingthetotalforceofforces l,2and3,aondition will be reached wherein the force of arm 33 (force 4) will be overbalaneed and hence, follower 17 will move toward a concentric position with respect to shaft 11 and the switch 24 will be actuated. If shaft 11 slows down, force 4 will eventually overbalance forces 1. 2 and3andfollowerl7willmovetoaneccentricpositionandswitchflwillagainbeectuatedintheoonosite direction.

To facilitate the slipping action hereinbefore described, the corners of the triangular member 15 are rounded, as shown, the rounded corners being referred to as bulbous bearingbosses. lfdesiredthedsiver'lilinstead ofcomprising a triangular plate 15 may comprise three circumferentially spaced radial arms spaced apart, the arms preferably having rounded outer ends which may resemble the bosses 1. In addition, the corners of the recess 18 are also rounded, being of a radius of curvature conforming to, but slightly larger than the radius of curvature of the bones 16. By providing the rounded contacting surfaces, described, the danger of wedging or jamming of the follower upon the driver is avoided.

The present invention may be considered in three degrees of breadth. Broadly, ,the present invention comprises a basic mechanical movement wherein a driving member moving at uniform rotation rotates a driven member at intermittent rotary motion wherein the members rotate about axes which move eccentrically with respect to each other. In another aspect of the present invention rotary movement of a driving and driven member is controllably changed to translatory movement to accomplish any desired function, and thirdly, a control device for actuating an electric switch in response to predetermined rotary speed of a body is contemplated.

In more specific aspects of the present invention the period at which the driven rotor or follower 17 moves radially can be controlled relative to the speed at which shaft 11 rotat. by changing the physical characteristics of the materiar 23, particularly its adhesiveness or shear strength. Also, the area of contact of the driving rotary and driven rotor with the material 23 may be changed to cause switch actuation in response to different speeds of rotation of shaft 11. All of these changes are contemplated in the present invention. In addition, the

degree of intermittent movement of follower "with respect to driver 13 may be changed by changing the dimensions of the driver 15 with respect to recess 18, within the limits hereinbefore set forth. .This will also effect the degree of radial movement of the follower. For instance, with a smaller driver 15 the frequency of the intermittent rotation of the follower will be decreased but the radial .movement of the driven rotor will increase, the bore 19 permitting and vice versa.

It can readily be seen that the present invention can be used for many purposes and all such uses are contemplated herein. Hence, I do not wish to be limited except as necessitated by the appended claims.

I claim as my invention:

1. A device for actuating an electric switch in response to the rate of rotation of a rotating body which comprises, a driving rotor which is rotatable about a predetermined axis, a driven rotor circumscribing said axis and rotatably and radially movably carried upon said driving rotor, said driven rotor being provided with a recess of substantially equilateral'triangular shape through which said axis passes, said driving rotor being positioned in said recess and comprising three radially extending contact members spaced substantially 120 apart, the outer ends of said contact members being at a distance from said axis of rotation greater than the distance between the center of said recess and the midpoint of one of the sides defining said recess, and the outer ends of said contact members being a lesser distance from each other than the greatest dimension of said recess, an electric switch disposed adjacent said driven rotor, resiliently impelled movable means carried by said switch for actuating said switch, said means being in contact with the periphery of said driven rotor and resiliently urging said driven rotor radially to an eccentric position with respect to the driving rotor, means for rotating said driving rotor to cause said contact members to exert a moment of force upon the sides of said recess to rotate said driven rotor and to exert frictional resistance upon said driven rotor to oppose the resilient force of said actuating means and move said actuating means to actuate said switch when a predetermined rate of rotation of said driving rotor is reached.

2. A device for actuating an electric switch in response to the rate of rotation of a rotating body which comprises, a driving rotor which is rotatable about a predetermined axis, a driven rotor circumscribing said axis and rotatably and radially movably carried upon said driving rotor, said driven rotor being provided with a recess of substantially equilateral triangular shape through which said axis passes, said driving rotor being positioned in said recess and comprising three radially extending contact members spaced substantially 120 apart, the outer ends of said contact members being at a distance from said axis of rotation greater than the distance between the center of said recess and the midpoint of one of the sides defining said recess, and the outer ends of said contact members being a lesser distance from each other than the greatest dimension of said recess, an electric switch disposed adjacent said driven rotor, a resiliently impelled movable actuating arm for actuating said switch, said arm being in contact with the periphery of said driven rotor and urging said driven rotor radially to an eccentric position with respect to the driving rotor, means for rotating said driving rotor to cause said contact members to exert a moment of force upon the sides of said recess to rotate said driven rotor and to exert frictional resistance upon said driven rotor to oppose the resilient force of said actuating arm and move said actuating arm to actuate said switch when said driving rotor reaches a predetermined rate of rotation.

3. A device for actuating an electric switch in response to the rate of rotation of a rotating body which comprises, a driving rotor which is rotatable about a predetermine'd axis, a driven rotor circumscribing said axis and rotatably and radially movably carried upon said rotor, a mastic material positioned between opposed surfaces of said rotors to augment the friction therebetween, said driven rotor being provided with a recess of substantially equilateral triangular shape through which said axis passes, said driving rotor being positioned in said recess and comprising three radially extending contact members spaced substantially apart, the outer ends-of said contact members being at a distance from said axis of rotation greater than the distance between the center of said recess and the midpoint of one of the sides defining said recess, and the outer ends of said contact members being a lesser distance from each other than the greatest dimension of said recess, an electric switch disposed adjacent said driven rotor, a resiliently impelled movable means car ried by said switch for actuating said switch, said means being in contact with the periphery of said driven rotor and resiliently urging said driven rotor radially to an eccentric position with respect to the driving rotor, means for rotating said driving rotor to exert frictional resist-- ance upon said driven rotor through the agency of said mastic material and cause said contact members to exert a moment of force upon the sides of said recess to rotate said driven rotor to oppose the resilient force of said actuating means and move said actuating means to actuate said switch when a predetermined rate of rotation of the driving rotor is reached.

4. A device for actuating an electric switch in response to the rate of rotation of a rotating body which comprises, a driving rotor which is rotatable about a predetermined axis, a driven rotor circumscribing said axis and rotatably and radially movably carried frictionally upon said driving rotor, said driven rotor being provided with a recess of substantially equilateral triangular shape through which said axis passes, said driving rotor being positioned in said recess and comprising a substantially equilateral triangle having contact bosses at the apices thereof spaced substantially 120 apart, the outer ends of said contact bosses being at a distance from said axis of rotation greater than the distance between the center of said recess and the midpoint of one of the sides defining said recess, and the outer ends of said contact bosses being a lesser distance from each other than the greatest dimension of said recess, an electric switch disposed adjacent said driven rotor, a resiliently impelled movable actuating arm for actuating said switch, said arm being -in contact with the periphery of said driven rotor and urging said driven rotor radially to an eccentric position with respect to the driving rotor, means for rotating said driving rotor to exert frictional resistance upon said driven rotor and cause said contact bosses to exert a moment of force upon the sides of said recess to rotate said driven rotor and to oppose the resilient force of said actuating arm and move said actuating arm to actuate said switch when a predetermined rate of rotation of the driving rotor is reached.

5. A device for converting rotary movement to radial movement in response to the rate of rotation of a rotating body which comprises, a driving rotor which is rotatable about a predetermined axis, a driven rotor circumscribing said axis and rotatably and radially movably carried frictionally upon said driving rotor, said driven rotor being provided with a recess of substantially equilateral triangular shape through which said axis passes, said driving rotor being positioned in said recess and comprising three radially extending contact members spaced substantially 120 apart, the outer ends of said contact members being at a distance from said axis of rotation greater than the distance between the center of said recess and the midpoint of one of the sides defining said recess, and the outer ends of said contact members being a lesser distance from each other than the greatest dimension of said recess, a member disposed adjacent her in contact with the periphery of said driven rotor to urge said driven rotor radially to an eccentric position with respect to the driving rotor, means for rotating said driving rotor to cause said contact members to exert a moment of force upon the sides of said recess to rotate said driven rotor and to exert frictional resistance upon said driven rotor to oppose the radial force of said member and move said member radially, when a predetermined rate of rotation of said driving rotor is reached.

6. A device for converting rotary movement to radial movement in response to the rate of rotation of a rotating body which comprises, a driving rotor which is rotatable about a predetermined axis, a driven rotor circumscribing said axis and rotatably and radially movably carried frictionally upon said driving rotor, said driven rotor being provided with a recess of substantially equilateral triangular shape through which said axis passes, said driving rotor being positioned in said recess and comprising three radially extending contact members spaced substantially 120' apart, the outer ends of said'contact members being at a distance from said axis of rotation greater than the distance between the center of said recessandthemidpointofoneofthesidesdefiningsaid recess, and the outer ends of said contact members being alesserdistancefromeachotherthanthegreatestdimension of said recess, a member disposed adjacent said driven rotor, resilient means for movably holding said member in contact with the periphery of said driven rotor resiliently to urge said driven rotor radially to an eccentric position with respect to the driving rotor, means for rotating said driving rotor to cause said contact members toexertamomentofforceuponthesidesofsaidreoess to rotate said driven rotor and toexert frictional resistance upon said driven rotor to oppose, the radial force of said member and move said member radially when a predetermined rate of rotation of said driving rotor is reached.

7. A mechanical movement for changing uniform rotary motion to intermittentrotary motion which comprises, a rotatable driving member, a driven member rotatable about an axis which is substantially parallel to, and radially eccentrically movable relative to the axis of rotation of the driving member, said driven member being provided with a recess of substantially equilateral triangular shape, said driving member comprising three equispaced radial contact members positioned in said recess and rotatable therein in frictional contact with said driven member, the outer ends of said contact members being at a distance from their axis of rotation greater than the distance between the center of said recess and the midpoint of one of the sides defining said recess, and the outer ends of said contact members being a lesser distance from each other than the greatest dimension of said recess, means for uniformly rotating said driving member to cause said contact members to exert a moment of force upon the sides of said recess to rotate said driven member and means for limiting radial movement of said driven member in a predetermined direction to hold the respective axes of rotation of said driving and driven members eccentric with respect to each other.

Reissues Ciel in the tile of this patent UNITED STATES PA' IENTS 2,382,228 Howell Aug. 14, 1945 

